1. Field of the Invention
The present invention relates to an improvement in the structure of an expansion valve mounting member used for connecting a block type expansion valve to a laminated heat exchanger in, for instance, an air conditioning system for vehicles.
2. Description of the Related Art
Structures in which a block type expansion valve is mounted in the vicinity of the intake/outlet portions of a laminated heat exchanger using an expansion valve mounting member in the known art include the one disclosed in Japanese Unexamined Patent Publication No. 64-28762.
To outline the structure in which an expansion valve is mounted to a laminated heat exchanger using an expansion valve mounting member in reference to this example, piping for coolant inflow and piping for coolant outflow are provided parallel to each other over a specific distance at the center in the direction of the lamination in the laminated heat exchanger. A plate-like coupling member is provided with an inflow piping connecting hole and an outflow piping connecting hole through the coupling member, which communicate with the piping for coolant inflow and the piping for coolant outflow respectively and on the circumferential edges of the inflow piping connecting hole and the outflow piping connecting hole, projected portions that fit into the piping for coolant inflow and the piping for coolant outflow are formed. On the side surface opposite from where the projected portions are provided in the plate-like coupling member, roughly cylindrical protrusions project out from the circumferential edges of the connecting holes. In addition, two through holes with an internal diameter which allows the cylindrical protrusions of the plate-like coupling member to be fitted therein, are formed in the block type expansion valve.
The following is an explanation of the mounting procedure for the block type expansion valve structured as described above. After fitting the piping for coolant inflow and the piping for coolant outflow to the projected portions of the plate-like coupling member, the protrusions of the plate-like coupling member are inserted inside the corresponding holes in the block type expansion valve and then the plate-like coupling member is secured to the block type expansion valve with screws.
However, the projected portions, the protrusions, the inflow piping connecting hole and the outflow piping connecting hole which constitute the plate-like coupling member in this prior art example, are manufactured by cutting them out from an aluminum material (the so-called full cutting method) and, as a result, the production costs for the plate-like coupling member are high. Also, another problem is that the method is not well suited to mass production.